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A Metallaphotoredox Strategy for the Cross-Electrophile Coupling of ?-Chloro Carbonyls with Aryl Halides.

ABSTRACT: Here, we demonstrate that a metallaphotoredox-catalyzed cross-electrophile coupling mechanism provides a unified method for the ?-arylation of diverse activated alkyl chlorides, including ?-chloroketones, ?-chloroesters, ?-chloroamides, ?-chlorocarboxylic acids, and benzylic chlorides. This strategy, which is effective for a wide variety of aryl bromide coupling partners, is predicated upon a halogen atom abstraction/nickel radical-capture mechanism that is generically successful across an extensive range of carbonyl substrates. The construction and use of arylacetic acid products have further enabled two-step protocols for the delivery of valuable building blocks for medicinal chemistry, such as aryldifluoromethyl and diarylmethane motifs.

SUBMITTER: Chen TQ

PROVIDER: S-EPMC6764888 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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A Metallaphotoredox Strategy for the Cross-Electrophile Coupling of α-Chloro Carbonyls with Aryl Halides.

Chen Tiffany Q TQ MacMillan David W C DWC

Angewandte Chemie (International ed. in English) 20190905 41

Here, we demonstrate that a metallaphotoredox-catalyzed cross-electrophile coupling mechanism provides a unified method for the α-arylation of diverse activated alkyl chlorides, including α-chloroketones, α-chloroesters, α-chloroamides, α-chlorocarboxylic acids, and benzylic chlorides. This strategy, which is effective for a wide variety of aryl bromide coupling partners, is predicated upon a halogen atom abstraction/nickel radical-capture mechanism that is generically successful across an exten ...[more]

PMID: 31410960

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